Object Pronouns are divided into Disjunctive Object Pronouns and Conjunctive Object Pronouns.[1]

When used as the object of a preposition, a personal pronoun is said to be in the disjunctive form or prepositional form (not used in conjunction with the verb).

m - masculine
f - feminine

Spanish Disjunctive Object Pronouns are used in a similar way as in English. See the examples below:

Ellos hablan de mí. - They speak of me.
Nosotros trabajamos para él. - We work for him.
Ella confía en tí. - She trusts you.
Usted se declara contra ellos. - You declare against them.

The direct and indirect object of verb may also be rendered by the pronoun in the Disjunctive form preceded by á, as:

We have then a double form for the pronouns used as direct and indirect object of verb--one Conjunctive, the other Disjunctive.

The Conjunctive form is that in general use.

The Disjunctive form is employed when emphasis or distinctness is required. It is seldom used alone,[3] Spaniards preferring to use it as a repetition after having used the Conjunctive form, as:

• Él me ama á mí.
  He loves me.

• Él nos vende á nosotros géneros estampados y á V. géneros de fantasía.
  He sells to us printed cloth and to you fancies.

• Yo le quiero ver á él y no á ella.
  I wish to see him and not her.

• Déle V. el dinero á él y los libros á ella.
  Give him the money and her the books.

• Dé V. el dinero á él y los libros á ella.
  Give him the money and her the books.